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Definition of Underbreak
1. Noun. (context: geology) Rock remaining within a specific excavation perimeter that should have been thrown out by the blast. ¹
¹ Source: wiktionary.com
|  | 
1. Noun. (context: geology) Rock remaining within a specific excavation perimeter that should have been thrown out by the blast. ¹
¹ Source: wiktionary.com